In recent years, next-generation display devices have been developed briskly, and attention has been focused on an organic light-emitting display device that uses an organic light-emitting element (organic EL (Electroluminescence) element) in which a first electrode, plural organic layers including a light emission layer, and a second electrode are sequentially laminated on a driving substrate. The organic light-emitting display device has such features that: a view angle is wide because it is of a self-light-emitting type; a backlight is not required and therefore power-saving can be expected; responsiveness is high; the thickness of the device can be reduced; and so on. Therefore, application to a large-screen display device such as a TV is strongly desired.
In order to increase the size and productivity of the organic light-emitting display device, use of a larger mother glass has been studied. At the time, in a method of forming a light-emission layer by using a general metal mask, light-emission layers of R, G and B are patterned by evaporating or applying a light-emitting material via a metal mask in which an opening pattern is provided on a metal sheet and therefore, it is necessary to increase the size of the metal mask according to a large substrate.
However, because of the upsizing of the metal mask, a deformation occurs due to the weight of the mask and thermal expansion at the time of evaporation is conspicuous and moreover, there arises such a problem that the accuracy of the opening pattern of the metal mask itself is reduced due to the upsizing and thus, patterning accuracy of the light-emission layer is also not achieved. Further, damage to the element due to contact between the metal mask and the substrate, and defect failure due to foreign matter on the mask become serious as the size increases. Therefore, a patterning technique requiring no metal mask is desired.
As maskless patterning methods for a large substrate, there are an ink-jet method (for example, see PLT 1) and a laser transfer method (for example, PLT 1 and PLT 3). The laser transfer method is a method of: forming a donor element in which a transfer layer including a light-emitting material is formed in a support member; disposing this donor element opposite a transferred substrate for forming an organic light-emitting element; and transferring the transfer layer to the transferred substrate by irradiating with a laser beam in a reduced pressure environment (see, for example, PLT 2 and PLT 3). With respect to a conventional mask deposition method, the laser transfer method has two advantages: definition can be made higher and a large substrate can be dealt with. In order to realize mass production of a large TV of organic EL, establishment of a manufacturing technique for the large substrate is considered to be necessary, and the laser transfer method can maintain the patterning accuracy constant with respect to the large substrate as well and thus is one of promising candidates for that.
In the laser transfer method, as illustrated in FIG. 39, within an effective region 810, display pixels Px1 made up of organic light-emitting elements 810R, 810G and 810B are formed in a matrix, and the display pixels Px1 of the same color are arranged in the same column. In the display pixels Px1 composed of the organic light-emitting elements 810R in the same column, a continuous red-light emission layer 815CR is formed by the laser transfer method. Similarly, in the display pixels Px1 composed of the organic light-emitting elements 810G in the same column, a continuous green-light emission layer 815CG is formed by the laser transfer method.